1. Field of the Invention
The present invention relates to an electrophotographic image forming apparatus such as a laser beam printer or a copying apparatus, and a process cartridge for use in such electrophotographic image forming apparatus.
2. Related Background Art
The electrophotographic image forming apparatus based on the electrophotographic image forming process executes selective exposure according to image information on an electrophotographic photosensitive member uniformly charged with charging means to form a latent image. Then it develops the latent image with toner in developing means to form a toner image, and transfers the toner image formed on the electrophotographic photosensitive member onto a recording sheet by transfer means to execute image formation.
For facilitating maintenance in such electrophotographic image forming apparatus, it is widely practiced to integrate the charging means, developing means or cleaning means with the electrophotographic photosensitive member as a process cartridge which is detachably mounted in the main body of the image forming apparatus.
In such image forming apparatus, image formation is achieved by conveying the recording sheet by paired rollers. For example, the recording sheet is pinched and conveyed by a convey roller driven by a motor through gears and an idler roller rotated in pressure contact with such convey roller, and the image is formed on such recording sheet by image forming means. A guide member is provided in the conveying direction of the above-mentioned paired rollers, in order to achieve exact conveyance of the recording sheet. In such recording sheet conveying means, there has been already known a guide member that can be retracted in case of sheet jamming, in order to facilitate removal of the jammed recording sheet.
The present invention is designed to further extend the prior technology.